Stripping the ends of wires or cables by hand is undesirable in situations where large numbers of such items must be stripped. In the aircraft manufacturing industry, for example, literally hundreds of thousands of wires are stripped each year by any given aircraft manufacturer. Automated wire stripping machines have been developed for types of wire other than multi-conductor, jacketed and shielded wire. Since there are significant differences in the many types of wires that must be stripped, a machine that is well-suited for stripping one type of wire may not be suited for another. Consequently, different kinds of specialized stripping machines have evolved over the years.
The present invention was designed with a view towards stripping a particular type of multi-conductor, twisted wire, jacketed and shielded cable. Basically, such cable is characterized in that it has two or more individually insulated wires that are twisted around each other. The twisted wires are surrounded by a braided metal shield or sheath, the latter being further surrounded by an outer jacket. The jacket tightly surrounds the underlying sheath and wires, and the twisted configuration of the wires imparts an irregular outer contour to the jacket. Such contour makes it difficult, if not impossible, to use conventionally-designed wire strippers for severing the jacket near the cable's end during a stripping operation without damaging the underlying shield.
A review of the prior art shows that most automated wire. stripping machines can be categorized into two groups: one group involves the use of cutting elements which are linearly driven into the insulation covering that is to be cut, typically from opposite sides of the conductor. Often times, the cutting elements have sharp edges that are sized to more or less correspond to the gauge of the wire being stripped. The second group involves a rotary severing action where one or more cutting elements are brought into contact with the insulation as they rotate about its outer circumference. Sometimes, the cutting elements are circular and have depth guides that prevent them from cutting into more than a certain depth of the insulation surrounding the wire. Both groups are typically used to strip wires having a circular outer circumference, and are not capable of stripping irregular wires or are otherwise not very well suited for such task.
The '632 patent cited above represents one attempt at developing a machine capable of stripping irregular cables. The present invention is a universal tool that provides a different approach to severing and stripping an irregular cable which is different from the approach disclosed in the '632 patent, and is believed to be different from other approaches disclosed in the prior art.